Precise position controlled actuating method and system

ABSTRACT

A system for actuating a spray pump assembly comprises a reference platform, a motor, a drive transmission, a spray pump holder, a force coupler, a force transducer, and a system controller. The motor receives a power and control input, and produces a rotary drive output. The drive transmission receives the rotary drive output and produces a linear drive output. The spray pump holder secures the spray pump assembly. The force coupler couples the linear drive output to the spray pump, and applies a force to the spray pump. The force transducer produces a force signal proportional to the force applied to the spray pump. The system controller receives a set of test inputs and provides the control input to the motor as a function of the set of test inputs. The system actuates the spray pump mechanism according to an actuation profile defined by the set of test inputs.

RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.10/176,930, filed Jun. 21, 2002 now U.S. Pat. No. 6,799,090 which claimsthe benefit of U.S. Provisional Application No. 60/299,874, filed Jun.21, 2001. The entire teachings of the above application are incorporatedherein by reference.

BACKGROUND OF THE INVENTION

The present invention relates to electromechanical actuators, and moreparticularly, to devices for providing precisely controlled actuation ofspray pump mechanisms.

The US Food and Drug Administration (FDA) strongly recommends automatedactuation of nasal spray devices subject to in-vitro bioequivalencetesting to decrease variability in drug delivery due to operator factors(including removal of potential analyst bias in actuation) and increasethe sensitivity for detecting potential differences between drugproducts. The FDA further recommends that an automated actuation systemhave settings or controls for actuation force, length of stroke,actuation velocity, hold time, return time, delay time betweensuccessive actuations, and actuation number. Selection of appropriatesettings should be relevant to proper usage of the nasal aerosol ornasal spray by the trained patient, and should be documented based onexploratory studies in which actuation force, actuation time, and otherrelevant parameters are varied. One such study includes “Guidance forIndustry: Bioavailability and Bioequivalence Studies for Nasal Aerosolsand Nasal Sprays for Local Action,” by Wallace P. Adams, U.S. Departmentof Health and Human Services, Food and Drug Administration, Center forDrug Evaluation and Research (CDER), June 1999.

Thorough characterization of the spray pump's performance in terms ofits emitted spray pattern, plume geometry and/or droplet sizedistribution are known to be affected by the means in which the spraypump is actuated. For example, slow actuation will likely cause pooratomization, producing a stream-like flow. Fast actuation will likelycause too fine a spray to be produced, leading to poor absorption in thenasal mucosa and unwanted inhalation and deposition of the droplets inthe throat and lungs.

From a mechanical perspective, over-actuation (forcing the spray pumpassembly beyond its intended stopping point) of the spray pump devicemust be avoided. If the spray pump mechanism is over-actuated, permanentdeformations can occur to the delicate pump orifice, swirl chambersand/or closure mechanisms, all of which can manifest themselves inhigher than expected variability in the pump's spray performance andflow characteristics. Further, rigidly holding the nozzle of the spraypump in place during actuation is vital to ensure that the spraydevelops properly and exits the nozzle normally so that measurements ofspray pattern, plume geometry and droplet size distribution are notartificially biased due to unwanted movement of the nozzle.

The Innova Systems (Pennsauken, N.J.) Nasal Spray Pump Actuators (NSPand eNSP) are prior art automated nasal spray actuators. Both models usethe same operating principle: a pneumatic cylinder connected to a solidplate (contact plate) is used to compress the spray pump against aspring loaded holding plate and clip mechanism. Typically, theseactuators are connected to a compressed air source and a computerinterface to allow a user to set the actuation force, contact force,holding time, and dose time for the actuation event. In operation, theseactuators adjust an air pressure regulator so that the pneumaticcylinder will first apply the prescribed contact force to the bottomside of the spray pump. Presumably, this application of the contactforce is done to minimize the time delay in producing the spray and/orto prevent the compression plate from striking the spray pump with adynamic load, which could damage the pump due to the high dynamic forcesachievable in the system. Next, the pressure regulator is adjusted againso that the pneumatic cylinder applies the prescribed actuation force(typically higher than the contact force). This action compresses thespray pump at a rate determined by the pneumatic efficiency of thesystem and the mechanical spring resistance of the spray pump and fluidcombination. The compression rate cannot be controlled. As a result,once the pressure regulator is set, the contact plate will move at arate determined by the system, not the user.

Experience with using these actuators has shown the followingdifficulties and shortcomings:

1. Lack of position and velocity controls leads to uncontrolled, “airhammer”—like performance with substantial spray pump over-actuation.This phenomenon has led to measurable degradation in spray pumpperformance over time and larger than expected variations in delivereddosage content. These problems are likely due to progressivedeterioration in the moving pump components due to over-actuation.

2. Lack of a nozzle holding mechanism leads to unwanted movements of thenozzle during actuation. This causes artificial distortions andsubstantial variability to appear in the associated spray pattern andplume geometry test data.

3. Difficulties associated with pneumatic control lead to oscillatingcontact force application and this leads to pre-spray droplets formingon the nozzle tip and measurable variability in spray pattern, plumegeometry, and droplet size distribution data.

4. Reliance on variable quality, laboratory compressed air sources leadsto inconsistent actuation performance and potential safety issues.

5. Uncertain actuation event-time triggering causes difficulty inacquiring time critical spray data such as spray pattern and plumegeometry.

6. Uncertain applied force measurements do not give a user confidencethat the actuator is applying the desired force to the spray pump.

7. Absence of recordable applied force and/or position/velocity datamake it difficult to chronicle the actuation event history.

SUMMARY OF THE INVENTION

In one aspect, a system for actuating a spray pump assembly including areservoir component and a pump/nozzle component comprises a referenceplatform, a motor component, a drive transmission component, a spraypump holder component, a force coupler, a force transducer, and a systemcontroller. The reference platform provides a foundation upon which thecomponents of the system are mounted. The motor component is fixedlyattached to the reference platform, receives a power input and a controlinput, and produces a rotary drive output therefrom. The drivetransmission component is fixedly attached to the reference platform,receives the rotary drive output and produces a linear drive outputtherefrom. The spray pump holder component is removably attached to thereference platform, and removably secures the spray pump assembly. Theforce coupler couples the linear drive output to the spray pumpmechanism, so as to apply a force to the spray pump mechanism. The forcetransducer produces a force signal proportional to the force applied tothe spray pump mechanism. The system controller receives a set of testinputs including (i) the force signal, (ii) one or more feedback signalsfrom the motor component, and (iii) user input corresponding to spraypump test parameters. The system controller provides the control inputto the motor component as a predetermined function of the set of testinputs. The system is operative to actuate the spray pump mechanismaccording to an actuation profile defined by the set of test inputs.

In one embodiment, the motor component includes a servomotor. In anotherembodiment, the servomotor includes a motor controller for receiving andprocessing the control input and for providing the one or more feedbacksignals, and for storing the actuation profile. The servomotor includesan encoder for monitoring the angular position of the rotary driveoutput and for producing an angular position signal corresponding to theangular position of the rotary drive output. The servomotor furtherincludes a driver for receiving the actuation profile from the motorcontroller and the power input, and for producing a drive signaltherefrom. The servomotor also includes an electric rotary motor forreceiving the drive signal and for producing the rotary drive outputtherefrom.

In another embodiment, the motor component includes any one of a varietyof stepper motors known in the art.

In another embodiment, the actuation profile includes a quiescentposition of the spray pump mechanism.

In another embodiment, the actuation profile includes a fully actuatedposition of the spray pump assembly.

In another embodiment, the actuation profile includes a velocity profilefrom a quiescent position of the spray pump assembly to a fully actuatedposition of the spray pump mechanism.

In another embodiment, the velocity profile includes velocity withrespect to time.

In another embodiment, the actuation profile includes a force profilefrom a quiescent position of the spray pump mechanism to a fullyactuated position of the spray pump mechanism.

In another embodiment, the force profile includes force with respect totime.

In another embodiment, the actuation profile includes a hold timeparameter corresponding to an amount of time the spray pump assembly isheld in a fully actuated position.

In another embodiment, the drive transmission component includes atleast one linear screw-rail assembly.

In another embodiment, the at least one linear screw-rail assemblyincludes an anti-backlash linear screw-rail assembly.

In another embodiment, the at least one linear screw-rail assemblyincludes a low friction coating on at least a screw component within thelinear screw-rail assembly.

In another embodiment, the low friction coating includes a Teflon-basedmaterial.

In another embodiment, the at least one linear screw-rail assemblyincludes ball bearing supports for supporting a screw component withinthe linear screw-rail assembly.

Another embodiment further includes a first pulley fixedly attached tothe rotary drive output, a second pulley fixedly attached to a screwcomponent within the linear screw-rail assembly, and a drive belt forcoupling the first pulley to the second pulley.

In another embodiment, the first pulley and the second pulley eachinclude a plurality of teeth, and the drive belt includes a plurality ofribs, such that in operation the teeth on the first pulley and the teethon the second pulley mesh with the ribs on the drive belt.

In another embodiment, the rotary drive output is directly coupled tothe drive transmission component.

In another embodiment, the spray pump holder component removably securesthe pump/nozzle component, and the coupler couples the linear driveoutput to the reservoir component.

In another embodiment, the spray pump holder component removably securesthe reservoir component, and the coupler couples the linear drive outputto the pump/nozzle component.

In another embodiment, the force transducer is disposed between thespray pump assembly and linear drive output.

In another embodiment, the force transducer is disposed between thespray pump assembly and the spray pump holder component.

In another embodiment, the force transducer is disposed between thespray pump holder and the reference platform.

In another embodiment, the system controller includes a digitalacquisition assembly for sampling an angular position signal thatcharacterizes the angular position of the rotary drive output, so as togenerate one or more digital samples corresponding to the angularposition signal. The system controller further includes a computersystem that receives the set of test inputs and the one or more digitalsamples, generates the actuation profile and provides the actuationprofile to the motor component. The computer system also receives theone or more feedback signals from the motor component and recording oneor more physical parameters of the spray pump assembly during actuation.

In another embodiment, the one or more physical parameters of the spraypump assembly includes a position versus time profile that describes theposition of the nozzle pump component with respect to the reservoircomponent as a function of time.

In another embodiment, the one or more physical parameters of the spraypump assembly includes a force versus time profile that describes forceapplied to the nozzle pump component with respect to the reservoircomponent as a function of time.

In another embodiment, the computer system performs a calibrationprocedure, calculates one or more compensation values, and uses thecompensation values to modify the one or more physical parameters.

In another embodiment, the computer system performs a calibrationprocedure, calculates one or more compensation values, and uses thecompensation values to modify the control input to the motor component.

In another embodiment, the system controller generates an actuationprofile representative of a human hand actuating the spray pumpassembly.

In another aspect, a method of actuating a spray pump via an actuatorsystem comprises removably securing the spray pump assembly to a spraypump holder component. The method further comprises determining (i) aquiescent position of the spray pump, and (ii) a fully actuated positionof the spray pump assembly. The method further comprises generating anactuation profile as a predetermined function of the quiescent position,the fully actuated position, and user input corresponding to spray pumptest parameters. The method also comprises actuating the spray pumpaccording to the actuation profile. The actuator system includes arotary motor driving a linear screw-rail assembly, thereby applying aforce to the spray pump assembly.

In another embodiment, the step of determining the quiescent position ofthe spray pump further includes measuring an amount of force applied tothe spray pump assembly, and advancing the linear screw rail assemblyuntil the amount of force applied to the spray pump assembly exceeds afirst predetermined value. The step of determining the quiescentposition of the spray pump assembly also includes recording a positionof the linear screw rail assembly when the amount of force applied tothe spray pump assembly exceeds the first predetermined value.

In another embodiment, the step of determining the fully actuatedposition of the spray pump assembly further includes continuing toadvance the linear screw rail assembly until the amount of force appliedto the spray pump assembly exceeds a second predetermined value. Thestep of determining the fully actuated position of the spray pumpassembly also includes recording a position of the linear screw railassembly when the amount of force applied to the spray pump assemblyexceeds the second predetermined value.

In another aspect, a spray pump holder for securing a spray pumpassembly includes a clamp having an aperture disposed about a centralaxis, and a plurality of fingers disposed about the perimeter of theaperture and extending out from the clamp parallel to the central axis.The spray pump holder also includes a compression member removablyattached to the clamp. The pump/nozzle component is inserted into theaperture along the central axis, and the compression member, whenattached to the clamp, compresses the plurality of fingers against thepump/nozzle component so as to secure the pump/nozzle component to theclamp.

In another embodiment, the clamp consists of a low friction material. Inone embodiment, the low friction material is Teflon.

In another embodiment, the compression member is constructed andarranged so as to variably compress the plurality of fingers against thepump/nozzle component.

In another embodiment, the clamp and the compression member includemating threads, such that the compression member screws into the clampand drives the fingers toward the central axis. In one embodiment, thecompression member consists of anodized aluminum.

Another embodiment of the spray pump holder further includes an annularinsert disposed about the central axis, between the fingers and thecentral axis. The pump/nozzle component is inserted through the annularinsert and the fingers compress the annular insert against thepump/nozzle component. In another embodiment, each of the fingers ischaracterized by a triangular cross section in a plane perpendicular tothe central axis.

In another embodiment, the clamp is characterized by a substantiallysquare body, disposed within a plane that is perpendicular to thecentral axis. In another embodiment, opposite sides of the square bodyslide into, or otherwise engage, corresponding grooves in a referenceplatform.

In another aspect, a spray pump holder for securing a spray pumpassembly comprises a bracket for supporting the spray pump assembly, andat least one securing strap for removably securing the spray pumpassembly against the bracket.

In another embodiment, the bracket includes a first cradle member havinga first engaging surface for retaining a first surface of the reservoircomponent, and a second cradle member having a second engaging surfacefor retaining a second surface of the reservoir component.

In another embodiment, the first engaging surface is substantiallyorthogonal to the second engaging surface.

In another embodiment, the first engaging surface includes a V-shapedsurface, so that the first engaging surface contacts a reservoircomponent having an arcuate exterior surface at two locations.

In another embodiment, the second engaging surface includes a V-shapedsurface, so that the second engaging surface contacts a reservoircomponent having an arcuate exterior surface at two locations.

In another embodiment, the bracket further includes an aperture,disposed between the first cradle member and the second cradle member,for accommodating a heel portion of the spray pump assembly.

Another embodiment of the spray pump holder further includes a firstsecuring strap and a second securing strap. The first securing strapsecures the spray pump assembly against the first cradle member, and thesecond securing strap secures the heel portion of the spray pumpassembly into the aperture and against the second cradle member. In oneembodiment of the spray pump holder, a first end of the at least onesecuring strap is fixedly attached to a first anchor on the bracket, anda second end of the at least one securing strap is removably attached toa second anchor on the bracket.

In another embodiment, the second end of the at least one securing straploops around the second anchor removably attaches to a distal portion ofthe securing strap.

In another aspect, a spray pump holder for securing a spray pumpassembly comprises a base including a body member, and a housing memberhaving a stop tab. The spray pump holder further includes a clampingassembly including a first lever and a second lever pivotally attachedat a pivot point about a pivot axle. The spray pump holder also includesa spring attached to the first lever and the second lever so as to forcetogether a first end of the first lever and a first end of the secondlever. The stop tab provides a platform or buttress, against which apump/nozzle component of a spray pump assembly presses, and thepump/nozzle component is secured between the first end of the firstlever and a first end of the second lever.

In another embodiment, the body member is characterized by a squarebody, and opposite sides of the square body slide into correspondinggrooves in a reference platform.

BRIEF DESCRIPTION OF DRAWINGS

The foregoing and other objects of this invention, the various featuresthereof, as well as the invention itself, may be more fully understoodfrom the following description, when read together with the accompanyingdrawings in which:

FIG. 1 shows a block diagram view of one preferred embodiment of asystem for providing precisely controlled actuation of spray pumpassembly;

FIG. 2A shows a nasal spray pump assembly in the quiescent position;

FIG. 2B shows a nasal spray pump assembly in the fully actuatedposition;

FIG. 2C shows an MDI spray pump assembly in the quiescent position;

FIG. 2D shows an MDI spray pump assembly in the fully actuated position;

FIG. 3A shows a perspective view of one embodiment of the actuatorsystem;

FIG. 3B is a sectional view of the system of FIG. 3A;

FIG. 3C is a bottom view of the system of FIG. 3A;

FIG. 4A shows the constituent pieces of the spray pump holder componentof the embodiment shown in FIG. 3A;

FIG. 4B shows a perspective view of the assembled spray pump holdercomponent secured to a spray pump assembly of FIG. 3A;

FIG. 5A is a perspective view of an MDI spray pump actuator;

FIG. 5B is a side sectional view of the embodiment of FIG. 5A;

FIG. 6A shows a perspective view of an MDI spray pump holder for theembodiment of FIG. 5A;

FIG. 6B shows an exploded view of the MDI spray pump holder of FIG. 6A;

FIG. 6C shows the spray pump holder securing the MDI spray pump assemblyof FIG. 6A;

FIG. 7A illustrates one example of an oral spray pump assembly;

FIG. 7B shows a perspective view of an alternate spray pump holderassembly secured to the oral spray pump assembly of FIG. 7A; and,

FIG. 7C shows an exploded view of the alternate spray pump holderassembly of FIG. 7B.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 shows a block diagram view of one preferred embodiment of asystem 100 for providing precisely controlled actuation of spray pumpassembly 102. The system includes a reference platform 104, a motorcomponent 106, a drive transmission component 108, a spray pump holdercomponent 110, a force transducer 112, and a system controller 114. Thereference platform 104 provides a substantially rigid platform uponwhich the various components of the system 100 may be mounted, andprovides a fixed reference from which the other components may relate toone another.

In general, the spray pump assembly 102 consists of two cooperativecomponents, and emits a spray plume when an applied force moves the twocooperative components relative to one another. In one embodiment thespray pump assembly 102 includes a reservoir component 120 and apump/nozzle component 122, as shown in FIG. 2A and FIG. 2B. FIG. 2Ashows the spray pump assembly 102 in the quiescent position, and FIG. 2Bshows the spray pump assembly 102 in the fully actuated position. Thespray pump assembly shown in FIGS. 2A and 2B is generally known in theart as a nasal spray pump assembly. The nasal spray pump emits a sprayplume 124 when the assembly transitions from the quiescent position tothe fully actuated position, and automatically returns to the quiescentposition. Another embodiment of the system 100 may be used to actuateanother type of spray pump assembly generally known as a metered doseinhaler (referred to herein as “MDI”), as shown in FIGS. 2C and 2D.Although the mechanics of the nasal spray pump assembly and the MDIdiffer significantly, the two cooperative components of the MDI will bereferred to herein as the reservoir component 120 and the pump/nozzlecomponent 122 as shown in FIGS. 2C and 2D for explanatory purposes only.Thus, FIG. 2C shows the spray pump assembly 102 in the quiescentposition, and FIG. 2D shows the spray pump assembly 102 in the fullyactuated position. The MDI emits a spray plume 124 when the assemblytransitions from the quiescent position to the fully actuated position,and automatically returns to the quiescent position.

The motor component 106 is mounted to the reference platform 104,receives a power input from an external power source (not shown) and acontrol input from the system controller 114, and produces a rotarydrive output dependent on the power and control inputs. In oneembodiment, the rotary drive output consists of a cylindrical shaftrotating about an axis of rotation, and may be instantaneouslycharacterized by an angular position, an angular velocity, an angularacceleration and a torque. The rotary drive output may include rotationin either direction (i.e., clockwise or counterclockwise), and mayinclude an angular velocity of zero (i.e., at rest—not rotating).

The drive transmission component 108 is also mounted to the referenceplatform 104 and receives the rotary drive output from the motorcomponent 106. The drive transmission component 108 transforms therotational motion of the rotary drive output into linear motion, so asto produce a linear drive output. In one embodiment, the linear driveoutput consists of a shaft traveling along a linear axis. In anotherembodiment, the linear drive output consists of a nut assembly travelingon a screw-rail along a linear axis. The linear drive output may beinstantaneously characterized by a linear position, a linear velocity, alinear acceleration and a linear force. The linear drive output mayinclude translation in either direction along the linear axis, and mayinclude a linear velocity of zero (i.e., at rest—not moving).

The spray pump holder 110 is removably attached to the referenceplatform 104 so that the spray pump holder 110 is held stationary withrespect to the reference platform 104 during system operation, but canbe removed and repositioned with relative ease (i.e., without specialtools or significant effort). The spray pump holder 110 is attached tothe reference platform 104 using any of a variety of techniques known inthe art, including but not limited to a friction engagement (e.g., pressfit), a threaded engagement (e.g., screw threads into a tappedaperture), a keyed latch fit, etc. Similarly, the spray pump holder 110removably secures the spray pump assembly 102. During operation, thespray pump assembly 102 is held stationary with respect to the referenceplatform 104 during system operation, but can be removed andrepositioned, or swapped with an alternate spray pump assembly withrelative ease.

The linear drive output from the drive transmission component 108 iscoupled to the spray pump assembly 102 via a “force coupler,” so thatduring operation, the linear drive output applies a force to the spraypump assembly 102. In one embodiment, this force coupler consists of adirect physical connection between the linear drive output and the spraypump assembly 102. In other embodiments, the coupling includes a linkagebetween the linear drive output and the spray pump assembly 102, such asa mechanical linkage, pneumatic linkage, hydraulic linkage, or othersimilar linkage, to redirect or otherwise condition the linear driveoutput.

The force transducer 112 produces a force signal that is proportional tothe amount of force delivered to the spray pump assembly 102, andprovides the force signal to the system controller 114 and the motorcomponent 106. The motor component 106 uses the force signal to detectdestructive force levels on the spray pump assembly 102. The motorcomponent 106 compares the force signal to a predetermined thresholdvalue, and reduces or eliminates the forces prior to damaging the spraypump assembly 102. In the embodiment shown in FIG. 1, the forcetransducer 112 is situated between the linear drive output and the spraypump assembly 102. Other embodiments of the system 100 may incorporatethe force transducer 112 between the spray pump assembly 102 and thespray pump holder 110, or between the spray pump holder 110 and thereference platform. In general, the force transducer 112 may be situatedanywhere that results in a force signal that is proportional to theamount of force delivered to the spray pump assembly 102.

The system controller 114 is electrically coupled to the motor component106 and the force transducer 112. The system controller 114 receives theforce signal from the force transducer 112 and feedback signals from themotor component 106. Among other data, the feedback signals from themotor component 106 provide information to the system controller 114regarding the angular position of the rotary drive output. The systemcontroller 114 also receives user input data that in part defines thedesired actuation profile to which the spray pump assembly is to besubjected. The actuation profile includes, but is not limited to,actuation velocity, actuation acceleration, initial actuation delay,actuation hold time, post-actuation delay, number of iterativeactuations, among others. Further, one unique actuation profile may beused for the upstroke (i.e., from quiescent position to fully-actuatedposition) and another unique actuation profile for the down-stroke(i.e., from the fully-actuated position to the quiescent position). Thesystem controller 114 also measures and records a plurality of pumpstroke statistics, including, but not limited to, distance required toachieve maximum velocity, distance at maximum velocity, distancerequired to stop from maximum velocity, time required to achieve maximumvelocity, time spent while at maximum velocity, time required to stopfrom maximum velocity, time required to reach the fully-actuatedposition, total time required for overall actuation, among others.

Another embodiment of the system 100 described in FIG. 1 is shown inFIGS. 3A, 3B and 3C. FIG. 3A shows a perspective view of the system 100(without the system controller 114), FIG. 3B is a sectional view of thesystem 100, showing internal components hidden by the shroud 138 in FIG.3A, and FIG. 3C is a bottom view of the system 100. This embodimentincludes a reference platform 104, a motor component 106, a drivetransmission component 108 (also referred to in this embodiment as a“linear screw-rail assembly”), a spray pump holder component 110, aforce transducer 112, a force coupler 130 (also referred to in thisembodiment as a “compression plate”), a drive coupler 132, two guiderods 134, and system controller 114. The interaction of these componentsis the same as for similarly numbered components in FIG. 1; however,this embodiment includes several components not shown in FIG. 1. Thecompression plate 130 couples the force generated by the linear driveoutput to the spray pump assembly 102. The compression plate 130 travelsalong two guide rods 134 that are fixedly attached to the referenceplatform 104 and are parallel to the spray axis 136. Thus, the directionof travel of the compression plate 130 is parallel to the spray axis136. The drive coupler 132 includes two pulleys and a drive belt. One ofthe pulleys is fixedly attached to the rotary drive output of the motorcomponent 106 (i.e., the motor spindle), so that the pulley rotatesalong with the motor spindle. The other pulley is fixedly attached tothe screw-rail spindle of the linear screw-rail assembly 108, so thatthe pulley rotates along with the screw-rail spindle. The drive beltcouples the two pulleys so that the two pulleys rotate synchronously. Inone embodiment, the pulleys have teeth or similar frictional ribs thatcorrespond to teeth or frictional ribs on the drive belt, so that inoperation the drive belt meshes with the pulleys to reduce or preventslippage. In other embodiments, the drive coupler 132 may include gearsrather than pulleys, and a drive chain rather than a drive belt, orother similar techniques known in the art for coupling rotationalmotion.

FIG. 4A shows the constituent pieces of the spray pump holder component110 of the embodiment shown in FIG. 3A, including a clamp 150, acompression member 152, and several annular inserts 154. FIG. 4B shows aperspective view of the assembled spray pump holder component 110secured to a spray pump assembly 102. The clamp 150 includes a squarebody 155, and an aperture 156 disposed about a central axis 158, throughwhich the pump/nozzle component of the spray pump assembly is inserted.The clamp 150 also includes a plurality of fingers 160 disposed aboutthe perimeter of the aperture 156. The fingers 160 are characterized bya triangular cross-section in the plane perpendicular to the centralaxis, and extend out from the clamp 150 in a direction parallel to thecentral axis 158, as shown in FIG. 4. In one embodiment, the clamp 150is made of Teflon, although other similar low-friction materials (e.g.,plastic, composite materials, or a rigid material coated with alow-friction material) may also be used. The compression member 152includes a disc-shaped body having an aperture 162 arranged such that aninterior surface 164 of the compression member 152 is slightly conical.In one embodiment the compression member 152 is made of anodizedaluminum, although other similar materials (e.g., plastic, steel, andother rigid metals and composite materials) may also be used. Thecompression member 152 engages the clamp 150 via mating threads 166, sothat the compression member 152 can be screwed into the clamp 150. Asthe compression member 152 so engages the clamp 150, the interiorconical surface 164 of the compression member 152 compresses the fingers160 inward toward central axis 158 and against the pump/nozzlecomponent. In one embodiment, the spray pump holder component 110 alsoincludes an annular insert 154 disposed about the central axis 158between the fingers 160 and the central axis 158, so that thepump/nozzle component is inserted through the annular insert 154. Inoperation, the fingers 160 compress the annular insert 154 against thepump/nozzle component. The square body 155 of the spray pump holdercomponent 110 is inserted into mating grooves 168 in the referenceplatform 104 (see FIG. 3A). The entire holder/spray pump assembly canthus be rotated along the spray axis in 90 degree increments to allowdifferent orientations of the emitted spray to be viewed by associatedspray characterization equipment.

In operation, a spray pump assembly 102 is inserted into the spray pumpholder component 110 and placed in the chassis so that the movement ofthe pump compression plate 130 is in line with the spray axis 136 of thespray pump assembly 102. The compression plate 130 moves along the guiderods 134 in the direction of the spray axis 136, driven by the rotationof the coupled motor and linear screw-rail spindles. The spray pumpholder component 110 holds the pump/nozzle component 122 stationary withrespect to the reference platform 104, and the compression plate 130moves the reservoir component 120 with respect to the pump/nozzlecomponent 122 to actuate the spray pump assembly 102.

The force transducer 112 is mounted within the compression plate 130 tomeasure the force applied to the pump by the movement of the compressionplate 130. One embodiment includes a separate contact plate 138,situated over the force transducer 112, that makes contact with thespray pump assembly 102 during actuation. In such embodiments the forcetransducer 112 is “sandwiched” between the contact plate and thecompression plate 130. In addition, the pump contact plate of thepresent invention is bolted to the top face of the force transducer.This subassembly is bolted halfway between the bearing mounts from belowon the compression plate. This arrangement positions the forcetransducer directly in-line with the direction of applied force, whileaccurately sandwiching the transducer between the compression plate andpump contact plate for optimal performance.

In the embodiment of FIGS. 3A and 3B, the motor component 106, thelinear screw-rail assembly 108 and the two guide rods 134 are mountedperpendicular to the reference platform 104 so that their spindles areparallel to one another. The cross-sections of the rotating spindle ofthe motor component 106, the screw-rail spindle of the linear screw-railassembly 108 and the two guide rods 134 in the plane of the referenceplatform 104 form a “Y” pattern. The motor spindle is positioned at thebottom of the “Y,” the screw-rail spindle is positioned at the fulcrumof the “Y,” and the two guide rods 134 are positioned at the oppositeends of the “Y” fork.

The embodiment of FIGS. 3A and 3B includes a serial data port 140 forfacilitating the transfer of user data corresponding to spray pump testparameters (e.g., programming instructions) from the system controller114 to the motor component 106. The serial port 140 further facilitatesthe transfer of feedback signals (e.g., status and motor shaft angularposition information) from the motor component 106 to the systemcontroller 112.

In the embodiment of FIGS. 3A and 3B, the system controller 114 includesa data acquisition assembly (referred to herein as a “DAQ”) and acomputer system. The DAQ receives and samples the angular positionsignal from the motor assembly 106 and to generate a series of digitalsamples corresponding to the angular position signal of the motor shaft.The DAQ is operated by control software resident in the computer system,and is primarily used to acquire and synchronize position data from themotor and force data from the force transducer 112. The computer systemreceives the user data corresponding to the spray pump test parametersand the signals from the DAQ. The computer system also generates anactuation profile from the user data, and provides the actuation profileto the motor component 106 via the serial port 140. The computer systemalso receives feedback signals from the motor component 106 and theforce signal from the force transducer 112, and from these signalsdetermines and records various physical parameters related to the spraypump assembly during the actuation event.

The Quicksilver Controls (Covina, Calif.) QCI-17-3 is an example of aprogrammable motor assembly suitable for use as the motor component 106in FIG. 3A. This motor assembly has an integrated digital signalprocessor (DSP), a 4000-line optical encoder, and drive electronics. TheDSP of this motor is capable of interpreting and executing programmingcommands that are used to digitally set the position, velocity andacceleration of the motor spindle while operating in closed-loopfeedback control with continuous input of the angular position signalfrom the optical encoder. In addition, the DSP of this motor is capableof executing commands and altering the position and/or velocity of thespindle every time a line on the optical encoder is detected, or 4000times per revolution (120 microseconds). The angular position signalfrom this optical encoder is compatible with the DAQ described herein.

The Kerk Motion (Hollis, N.H.) SRZ3DU4025T is an example of a linearscrew-rail assembly suitable for use as a drive transmission component108 of FIG. 3A. This linear screw-rail assembly has a Teflon-coated leadscrew and slide mechanism and ball bearing supports to reduce friction.In addition, this assembly incorporates a spring-loaded, anti-backlashpower nut design to provide positive engagement between the threads onthe lead screw and power nut drive mechanisms in both forward andbackward movements.

The Sensotec (Columbus, Ohio) 31 is an example of a force transducersuitable for use as the force transducer 112 of FIG. 3A. This forcetransducer has a sensitivity range of 0 to 50 pounds of force. Inaddition, when coupled with the UV signal conditioner also fromSensotec, it forms an integrated sensor package with high-level voltagesignal outputs compatible with the DAQ described herein.

The York Industries (Garden City Park, N.Y.) 172-2GT-09 and22-2GT09-1A-3/16 are an example of a drive belt and pulley combination,respectively, suitable for use as the drive coupler 132 of FIG. 3A. Thispulley and belt combination is designed to mesh with one another tominimize slip between the drive spindles on the motor and linearscrew-rail assemblies.

The National Instruments Corporation (Austin, Tex.) PCI-6023E is anexample of a DAQ suitable for use as the DAQ described herein for thesystem controller 114 of FIG. 3A. This DAQ board can simultaneouslysample and synchronize the angular position signal from the opticalencoder of the electric motor assembly and the force signal from theforce transducer 112. In addition, this DAQ board is designed to operatein a standard personal computer.

The Dell Computer Corporation (Round Rock, Tex.) Dimension XPS R400 isan example of a computer system suitable for use as part of the systemcontroller 114 of FIG. 3A. The serial port of this computer systemprovides a communications interface compatible with the DSP of the motorcomponent 106. In addition, this computer system is compatible withPCI-6023E DAQ and the control software described herein.

The control software written for and executed by the computer system inthe system controller 114 is designed to perform the followingfunctions:

1. Verify the proper operation of the motor, force transducer and DAQboard, in addition to diagnostic checks of other system components.

2. Step the user through calibration procedures, calculates calibrationconstants and incorporates those calibration constants into the system.

3. Automatically characterizes the spray pump assembly by determiningthe length of stroke and spray pump assembly bottom position (i.e.,quiescent position).

4. Allow a user to specify the actuation profile in terms of velocity,acceleration and hold time, among other parameters.

5. Allow the user to specify the event triggering mode as eitherinternal (i.e., controlled by the software) or external to the system(i.e., slaved to an external trigger source).

Another embodiment of the invention, used to actuate MDI assemblies, isshown in FIGS. 5A and 5B. FIG. 5A is a perspective view of thisembodiment, and FIG. 5B is a side sectional view of this embodiment. Inthis embodiment, the spray pump holder 110 secures the pump/nozzlecomponent 122 of the spray pump assembly 102 (i.e., the MDI assembly) tothe reference platform 104 as shown. Refer to FIGS. 2C and 2D for theconstituent components of the MDI type of spray pump assembly. Inoperation, the force coupler 130 moves in a downward motion (i.e., inthe direction of the arrow 180 in FIG. 5B) to actuate the spray pumpassembly 102. A compression finger 182, analogous to the contact plate138 in the embodiment of FIG. 3A, makes contact with the reservoircomponent 120 of the spray pump assembly and applies the actuatingforce. FIG. 5B shows the motor component 106 directly coupled to thedrive transmission component 108 (a single linear screw-rail assembly inthis embodiment) via a direct drive coupling 132, in contrast to thepulley and belt drive coupling of the FIG. 3A embodiment. The embodimentshown in FIGS. 5A and 5B includes a second linear screw-rail assembly184 that operates in conjunction with a tilt rail 186 to tilt the upperportion of the actuator system with respect to the base member 188. Thesecond linear screw-rail assembly 184 is attached to the referenceplatform 104. A first end of the tilt rail 186 is pivotally attached tothe nut component 187 of the linear screw-rail assembly 184, and thesecond end of the tilt rail 186 is pivotally attached to a pivot point190 on the base member 188. As the nut component 187 translates alongthe screw rail portion of the screw rail assembly 184, the tilt rail 186forces the upper portion of the actuator system to pivot on a secondpivot point 192 on the base member 188. A positioning knob 194 on thetop surface of the upper portion of the actuator system is mechanicallycoupled to the second linear screw-rail assembly 184. As the positioningknob 194 is turned, the nut component 187 travels linearly along thescrew rail assembly 184.

For use in spray plume imaging systems, ideally the spray axis 136 fromthe spray pump assembly 102 is parallel to the base member 188, i.e.,the spray axis 136 exactly horizontal to the working surface upon whichthe system sits. Since MDI spray pump assemblies are not manufactured toany standard form factor, the embodiment shown in FIGS. 5A and 5B can beadjusted, via the positioning knob 194, the second linear screw railassembly 184 and the tilt rail 186, until the spray axis 136 is parallelto the base member 188. Thus, in general, the positioning knob 194, thesecond linear screw rail assembly 184 and the tilt rail 186 may be usedto adjust the angle of the spray axis 136 with respect to an externalreference plane. Other techniques known in the art may also be used toadjust the spray axis 136. For example, a simple arcuate sliding bracketwith a locking nut may be used to tilt the system with respect to theworking surface, or an external tilting platform may be interposedbetween the actuating system and the working surface to vary theattitude of the spray axis 136. Further, the angle of the spray pumpholder 110 may be adjusted with respect to the reference platform 104 tovary the angle of the spray axis 136 with respect to the workingsurface.

A perspective view of the spray pump holder 110 for the embodiment ofFIGS. 5A and 5B is shown in FIG. 6A. An exploded view of the spray pumpholder of FIG. 6A is shown in FIG. 6B. FIG. 6C shows the spray pumpholder securing the MDI spray pump assembly of FIG. 6A. The spray pumpholder 110 for this embodiment includes a bracket 200 for supporting theMDI spray pump assembly and at least one securing strap 202 for securingthe spray pump assembly against the bracket 200. The bracket 200includes a first engaging surface 204 for retaining the back surface ofthe spray pump assembly, and a second engaging surface 206 for engagingthe bottom surface of the spray pump assembly. In one embodiment, thefirst engaging surface is substantially orthogonal to the secondengaging surface 206, so as to be compatible for retaining substantiallyorthogonal surfaces on an MDI spray pump assembly. In other embodiments,the first engaging surface 204 and the second engaging surface 206 arecharacterized by a V-shaped surface so as to readily retain arcuatesurfaces of the spray pump assembly. In one embodiment, the bracketfurther includes an aperture 208 between the first engaging surface 204and the second engaging surface 206. The aperture 208 accommodates a“heel” portion of the MDI spray pump assembly. The embodiment shown inFIGS. 6A and 6B includes two securing straps 202; an upper securingstrap 202 a and a lower securing strap 202 b. In operation, the uppersecuring strap 202 a wraps around the upper portion of the MDI spraypump assembly to secure the back surface of the MDI spray pump assemblyto the first engaging surface 204. The lower securing strap 202 b wrapsaround the lower portion of the MDI spray pump assembly to secure thebottom surface to the second engaging surface 206, with the heel of theMDI spray pump assembly through the aperture 208. The bracket 200further includes a first pair of anchors 210 for the upper securingstrap 202 a and a second pair of anchors 210 for the lower securingstrap 202 b. For each securing strap 202, one end is fixedly attached toone of the anchors 210, and the other end is removably attached to theother anchor 210. In one embodiment, the removably attached end of thesecuring strap 202 loops around the anchor and removably attaches toitself via Velcro or other similar securing mechanism. Other embodimentsmay secure the MDI spray pump assembly to the bracket 200 using alatching configuration similar to a “ski-boot” securing mechanism wellknown in the art.

In one embodiment of the actuator system 100 shown in FIG. 3A, analternate spray pump holder assembly 310 may be used to actuate an oralspray pump assembly. FIG. 7A illustrates one example of such an oralspray pump assembly 302, including a reservoir component 304 and apump/nozzle component 306. FIG. 7B shows a perspective view of thealternate spray pump holder assembly 310 secured to an oral spray pumpassembly 302 and mounted to the actuator of FIG. 3A. FIG. 7C shows anexploded view of the alternate spray pump bolder assembly 310 of FIG.7B. The assembly 310 includes a base 312 and a clamping assembly 314.The clamping assembly 314 is a spring-loaded “clothespin” type mechanismthat grasps the top of the pump/nozzle component 306. The clampingassembly 314 includes a first lever 318 and a second lever 320 pivotallyattached at a pivot point 322 via a pivot axle 323. A spring 324 isattached to the first lever 318 and the second lever 320 so as to forcea first end 326 of the first lever 318 and a first end 328 of the secondlever 320 together, thereby grasping the pump/nozzle component 306. Thebase 312 includes a housing member 330 and a square body 316. Thehousing member 330 includes a stop tab 332 against which the top of thepump/nozzle component 306 rests. The stop tab 332 applies resistingforce to the top of the pump/nozzle component 306 as the spray pumpassembly 302 is actuated. The clamping assembly 314 is attached to thebase 312, and the base 312 is removably attached to the referenceplatform 104 of the actuator system. The base 312 includes a square body316 that is inserted into the mating grooves 168 of the referenceplatform.

The core elements the actuating system described herein can not only beused to actuate nasal and oral spray pump assemblies and MDI spray pumpassemblies, but rather they should be considered as forming a highprecision, position controlled compression apparatus that can be used ina variety of automated actuation applications. Examples of otherapplications may include, but are not limited to: automated actuation ofnasal syringes; testing of automotive fuel injectors; robotic actuationof industrial nozzles; and/or actuation of cosmetic spray pumps.

A user manual related to a nasal spray pump actuator embodiment isincluded as Appendix A of U.S. application Ser. No. 10/176,930. A usermanual related to an MDI spray pump actuator embodiment is included asAppendix B of U.S. application Ser. No. 10/176,930.

The invention may be embodied in other specific forms without departingfrom the spirit or essential characteristics thereof. The presentembodiments are therefore to be considered in respects as illustrativeand not restrictive, the scope of the invention being indicated by theappended claims rather than by the foregoing description, and allchanges which come within the meaning and range of the equivalency ofthe claims are therefore intended to be embraced therein.

1. A system for actuating a spray pump assembly, the system comprising:a motor component for receiving a power input and a control input andproducing a rotary drive output therefrom; a drive transmissioncomponent for receiving the rotary drive output and producing a lineardrive output therefrom; a spray pump holder component for removablysecuring the spray pump assembly; a force coupler for coupling thelinear drive output to the spray pump mechanism, so as to apply a forceto the spray pump mechanism; a force transducer for producing a forcesignal proportional to the force applied to the spray pump mechanism;and a system controller for receiving a set of test inputs including (i)the force signal, (ii) one or more feedback signals from the motorcomponent, and (iii) user input corresponding to spray pump testparameters, and providing the control input to the motor component as apredetermined function of the set of test inputs; wherein the system isoperative to actuate the spray pump mechanism according to an actuationprofile defined by the set of test inputs.
 2. The system of claim 1wherein the spray pump holder comprises: (i) a clamp having an aperturedisposed about a central axis, and a plurality of fingers disposed aboutthe perimeter of the aperture and extending out from the clamp parallelto the central axis; (ii) a compression member removably attached to theclamp; wherein the pump/nozzle component is inserted into the aperturealong the central axis, and the compression member, when attached to theclamp, compresses the plurality of fingers against the pump/nozzlecomponent so as to secure the pump/nozzle component to the clamp.
 3. Thesystem of claim 2 wherein the clamp consists of a low friction material.4. The system of claim 3 wherein the low friction material is Teflon. 5.The system of claim 2 wherein the compression member is constructed andarranged so as to variably compress the plurality of fingers against thepump/nozzle component.
 6. The system of claim 2 wherein the clamp andthe compression member include mating threads, such that the compressionmember screws into the clamp and drives the fingers toward the centralaxis.
 7. The system of claim 2 wherein the compression member consistsof anodized aluminum.
 8. The system of claim 2 further including anannular insert disposed about the central axis, between the fingers andthe central axis, wherein the pump/nozzle component is inserted throughthe annular insert and the fingers compress the annular insert againstthe pump/nozzle component.
 9. The system of claim 2 wherein each of thefingers is characterized by a triangular cross section in a planeperpendicular to the central axis.
 10. The system of claim 2 wherein theclamp is characterized by a substantially square body disposed within aplane perpendicular to the central axis.
 11. The system of claim 10wherein opposite sides of the square body slide into correspondinggrooves in a reference platform.
 12. The system of claim 1 wherein thespray pump holder comprises: (i) a bracket for supporting the spray pumpassembly, and (ii) at least one securing strap for removably securingthe spray pump assembly against the bracket.
 13. The system of claim 12wherein the bracket includes a first cradle member having a firstengaging surface for retaining a first surface of the reservoircomponent, and a second cradle member having a second engaging surfacefor retaining a second surface of the reservoir component.
 14. Thesystem of claim 13 wherein the first engaging surface is substantiallyorthogonal to the second engaging surface.
 15. The system of claim 13wherein the first engaging surface includes a V-shaped surface, so thatthe first engaging surface contacts a reservoir component having anarcuate exterior surface at two locations.
 16. The system of claim 13wherein the second engaging surface includes a V-shaped surface, so thatthe second engaging surface contacts a reservoir component having anarcuate exterior surface at two locations.
 17. The system of claim 13wherein the bracket further includes an aperture, disposed between thefirst cradle member and the second cradle member, for accommodating aheel portion of the spray pump assembly.
 18. The system of claim 12further including a first securing strap and a second securing strap,wherein the first securing strap secures the spray pump assembly againstthe first cradle member, and the second securing strap secures the heelportion of the spray pump assembly into the aperture and against thesecond cradle member.
 19. The system of claim 12 wherein a first end ofthe at least one securing strap is fixedly attached to a first anchor onthe bracket, and a second end of the at least one securing strap isremovably attached to a second anchor on the bracket.
 20. The system ofclaim 19 wherein the second end of the at least one securing strap loopsaround the second anchor removably attaches to a distal portion of thesecuring strap.
 21. The system of claim 1 wherein the spray pump holdercomprises: (i) a base including a body member, and a housing memberhaving a stop tab; and (ii) a clamping assembly including a first leverand a second lever pivotally attached at a pivot point about a pivotaxle, and a spring attached to the first lever and the second lever soas to force together a first end of the first lever and a first end ofthe second lever; wherein the stop tab provides a platform against whicha pump/nozzle component of a spray pump assembly presses, and thepump/nozzle component is secured between the first end of the firstlever and a first end of the second lever.
 22. The system of claim 21wherein the body member is characterized by a square body, and oppositesides of the square body slide into corresponding grooves in a referenceplatform.
 23. A method of actuating a spray pump assembly including areservoir component and a pump/nozzle component, via an actuator systemincluding a rotary motor driving a linear screw rail assembly, therebyapplying a force to the spray pump assembly, the method comprising:removably securing the spray pump assembly to a spray pump holdercomponent; determining (i) a quiescent position of the spray pump, and(ii) a fully actuated position of the spray pump assembly; generating anactuation profile as a predetermined function of the quiescent position,the fully actuated position, and user input corresponding to spray pumptest parameters; and actuating the spray pump according to the actuationprofile wherein determining the quiescent position of the spray pumpfurther includes (i) measuring an amount of force applied to the spaypump assembly, (ii) advancing the linear screw rail assembly until theamount of force applied to the spray pump assembly exceeds a firstpredetermined value and (iii) recording a position of the linear screwrail assembly when the amount of force applied to the spray pumpassembly exceeds the first predetermined value.
 24. A method accordingto claim 23, wherein determining the fully actuated position of thespray pump assembly further includes (i) continuing to advance thelinear screw rail assembly until the amount of force applied to thespray pump assembly exceeds a second predetermined value, and (ii)recording a position of the linear screw rail assembly when the amountof force applied to the spray pump assembly exceeds the secondpredetermined value.